:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --ink: #16181d;
  --muted: #5f6672;
  --line: #e3e6ea;
  --accent: #2f5bea;
  --accent-ink: #ffffff;
  --err-bg: #fdecec; --err-ink: #98221f; --err-line: #f3c9c7;
  --ok-bg: #e9f6ee;  --ok-ink: #1c6b3f;  --ok-line: #c3e6d1;
  --radius: 12px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115; --card: #171a21; --ink: #e9ecf1; --muted: #99a1b0; --line: #262b35;
    --accent: #6b8dff; --accent-ink: #0f1115;
    --err-bg: #2a1a1b; --err-ink: #f3b6b3; --err-line: #4a2a2b;
    --ok-bg: #14251c;  --ok-ink: #a7dcbd;  --ok-line: #26452f;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0; min-height: 100vh; display: grid; place-items: center; padding: 24px;
  background: var(--bg); color: var(--ink);
  font: 15px/1.55 ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
.card {
  width: 100%; max-width: 420px; background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px; box-shadow: 0 1px 2px rgba(0,0,0,.04), 0 8px 24px rgba(0,0,0,.06);
}
.brand { display: flex; align-items: center; gap: 12px; margin-bottom: 22px; }
.mark {
  width: 42px; height: 42px; display: grid; place-items: center; flex: none;
  border-radius: 10px; background: var(--accent); color: var(--accent-ink);
}
.brand-name { font-weight: 650; letter-spacing: -0.01em; }
.brand-sub { color: var(--muted); font-size: 13px; }
h1 { font-size: 21px; line-height: 1.25; margin: 0 0 6px; letter-spacing: -0.02em; }
.lede { color: var(--muted); margin: 0 0 18px; }
label { display: block; font-size: 13px; font-weight: 550; margin: 14px 0 6px; }
input[type=email], input[type=password] {
  width: 100%; padding: 10px 12px; font: inherit; color: var(--ink);
  background: var(--bg); border: 1px solid var(--line); border-radius: 8px;
}
input:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; border-color: transparent; }
button, .button {
  display: inline-block; width: 100%; margin-top: 20px; padding: 11px 16px; text-align: center;
  font: inherit; font-weight: 600; color: var(--accent-ink); background: var(--accent);
  border: 0; border-radius: 8px; cursor: pointer; text-decoration: none;
}
button:hover, .button:hover { filter: brightness(1.06); }
.hint { color: var(--muted); font-size: 13px; margin: 10px 0 0; }
.alert { padding: 10px 12px; border-radius: 8px; font-size: 14px; margin: 0 0 16px; border: 1px solid; }
.alert.error { background: var(--err-bg); color: var(--err-ink); border-color: var(--err-line); }
.alert.ok    { background: var(--ok-bg);  color: var(--ok-ink);  border-color: var(--ok-line); }
.settings { list-style: none; padding: 0; margin: 22px 0 0; border-top: 1px solid var(--line); }
.settings li { display: flex; justify-content: space-between; gap: 12px; padding: 9px 0; border-bottom: 1px solid var(--line); font-size: 13px; }
.settings span { color: var(--muted); }
.settings code { font: 12.5px/1.4 ui-monospace, SFMono-Regular, Menlo, monospace; }
.foot { margin: 20px 0 0; display: flex; justify-content: space-between; align-items: center; font-size: 14px; }
.foot a { color: var(--accent); }
.inline { display: inline; }
button.link {
  width: auto; margin: 0; padding: 0; background: none; color: var(--accent);
  font-weight: 400; text-decoration: underline; cursor: pointer;
}